The first cryptocurrency you should hold should be bitcoin. You should also look at smart contract based coin and focus on buying the one you believe ...
source https://www.google.com/url?rct=j&sa=t&url=https://bitcointalk.org/index.php%3Ftopic%3D5045289.80&ct=ga&cd=CAIyGmM2Nzk3ODA2ZWViNjVjODI6Y29tOmVuOlVT&usg=AFQjCNF1VLqpBXtXU3o1vn4DfvUI38OJ0w
